Is the mean and variance of the coco dataset calculated?

[ShellyLingling]

class COCO(data.Dataset):
    num_classes = 80
    default_resolution = [512, 512]
    mean = np.array([0.40789654, 0.44719302, 0.47026115],
                   dtype=np.float32).reshape(1, 1, 3)
    std  = np.array([0.28863828, 0.27408164, 0.27809835],
                   dtype=np.float32).reshape(1, 1, 3)

https://github.com/CaoWGG/CenterNet-CondInst/blob/1755e1752301e08363472b5e45c90723111877e9/src/lib/datasets/dataset/coco.py/L13-L19